Last few days, oil pressure guage does not move, and red light stays on for 3-4 seconds, then gauge comes up to normal reading when starting. Now today, started engine and press. came up to 6 (half way)on dial at idle and up to 3/4 when revved. Noticed when I turned lights off that ALL the gauges went DOWN by about 3 needles width. Investigated further and found that could vary readings by adjusting panel light dimmer. Do I have a bad earth in the instrument console ? Does not vary with others loads ie. heated rear screen, fog lights etc. Anyone had similar experiences. Is there a voltage regulator for the instruments? Car is having engine oil change in morning so will see if that helps with initial lag when starting although engine is not rattly or noisy suggesting maybe a sender or linked to above symptoms. Any suggestions appreciated, Thanks
